Clamp-bolt lock



F. LUMMER CLAMP BOLT LOCK Filed June 30. 1922 INVENTOR.

FY50 Lam/ 45R Patent ed July 31, 1923.

UNITED. STATES FRED LUMMER, or MILWAUKEE, WISCONSIN? CLAMP-BOLT LooK.

,Application filed mn'e'so, 1922. Serial No; 571,847. f j' To all whOm it may concern: y Be it known that I, FREDL MMER, a citizen of the United States, and resident of Milwaukee, in the county ofM-ilwaukee and State of lVisoonsin, have invented new and useful Improvements in Clamp-Bolt Locks, oi which the following is a description, reference being had to the accompanying drawing, which is a part of this specification.

This invention'relates to certain new and useful improvements in clamp bolt, locks.-

In that style of clamp employed for attaching motors to row boats and the like considerable diiiiculty has been experienced in preventing loosening of the clamping means by reason of the motor yibration causing retrograde movement of the clamp bolt. As a result many motors have been lost and if salvaged at all, done so only at considerable expense. v

Therefore, having this in mind it is one of the objects of myinvention to provide means engageable with the clamp bolt whereby the same is positively held against retrograde movement and at the same time may be readily released to permit the unscrewing of the bolt.

It is another object of this invention to provide a clamp bolt lock which is adapted for use not only in connection with that type of clamp employed for attaching a portable motor to a boat but may be employed in any type of clamp as for instance the C-clamp commonly utilized in securing work to a drill press or lathe where it is especially desirable to firmly secure thework against shifting by the vibration ofthe machine.

It is a further object of my invention to provide a device of the character described in which the locking member is at all times yieldably urged to engage in the slots or recesses of the clamping bolt and which may be readily moved and held against the action of its spring to permit the free rotation of the clamp bolt in either direction.

- A still further object of this invention resides in the provision of a device of the character described which may bereadily embodied in any type of clamp construction or may be employed where it is desired to prevent retrograde movement of a bolt member.

lVith the above and other objects in view which will appearas the description proceeds, my invention resides in the novel con.-

str uction,combination and arrangement of r I parts substantially as hereinafter described and more particularly defined by thejappended claim it being'understood that such changes in the. precise-embodiment of the herein disclosed invention maybe made as come within the scope of the claim.

In the accompanying drawing, I have illustrated one complete example of vthe physical embodiment ofmyinventionronstructed 'according'to the/best mode l havel so far devisedfor the practical application",

of the principles thereof, andin which:

l igure l is aside view of that type'of clamp more especially designed for attache .ing a portable motor to a boat, a portion of the clampbeing broken away and insection, E 1gure-2 is anenlargedfragmentary view taken through Figurejl on the plane ofthe line 2-2, and

Figure 3 is a View similar to .F igure, 2 illustrating a slightly modified construction proper alinement by reason of its shape. Referring now more particularly to the accompanying drawing, the numeral 5 'designates the rear end wall of a boat to which wherein the locking plunger is retained in cured a screw clamping bolt 9, the inner end i of which carries a cap 10 for engagement with the wall 5 to secure the same. firmly against th'efother arm 11 of the clamp The outer end of bolt9 is" provided with a Winged part 12 or the likeior convenience inrotating the same and the shank of the bolt. has one or more longitudinally extending slots 13 one wall 14 of which is tangentially arranged with respect to animaginarycircle havingthe axis of the bolt 9 as its center and the other wall 15 of which forms a continuation of an imaginary line passing through the axis of the bolt, the wall 15 being on the far side ofthe slot when the bolt is being unscrewed.

The outer end 16 of the arm 7 is longitudinally bored, as at 17, transversely of bore v8 and communicating therewith, the

outer end thereof'being counter-bored or enlarged, as at 18, and closed by a removable cap member 19. 'The cap member 19 is centrally bored, as at 20, and has a plunger 21 projected therethrough and through bore 17 to permit engagement of its "inner end 22 in slot 13. l

The plunger is yieldably urged to engage'its inner end With the bolt at all times by a spring23 coiled about the plunger within counter-bore 18 and having'one end engaging against the inner face of the cap member and its other end engaging againstv a'collar 24 fixed to the plunger. End 22 of the plunger, is shaped to fit slot 1-3 so that When engaged therein well if) cooperates with the side of the plunger end engaging the same to positively lock the bolt against retrograde movement, and at the 'sa metime, permit its rotation in the other ofthe slot and thus rendered inoperative, and 1n Figure 3 I accomplish this purpose by constructing bore 17 rectangular in cross section and shaping the inner end of the plunger to fit. In figure 2 this end is ac-- complished by a pin 25 Which is carried by the outer portion of the plunger and is en 'gageable in a slot or recess 26 communicating with a bore of the cap member. I Pin 25 not only holds the plunger in proper alinement' but permits the same to be rendered inoperative by pulling the plunger out- Wardly'against the force of its spring and then rotating the same to disaline its pin with recess 26, as Will be readily apparent. To permit the ready manipulation of the lun er a can or end 27 is secured to its outer end. I

What I claim as my invention:

. In a bolt look, a bolt provided With longitudinally extending slots a transversely disposed spring pressed punger adapted to engage said slots to prevent retrograde movement; oi the bolt a pin carried by the plunger adapted, to cooperate with a slot in the member through which the bolt is threaded to restrain the plunger from rotation,'and' a cap on the outer end. of the plunger, sald plunger belng held out of engagement Withthe bolt by moving said cap outwardly to disengage thepin fromitsslot and then partially rotating the cap to dis} align said pinand slot., I

In testimony whereof I Inv signature.

FRED LUMMER. 

